2,000 Dead Blackbirds: Why Do Birds Die in Big Groups?

At 11:30 pm this New Year's Eve in Beebe, Arkansas, red-winged blackbirds suddenly began to drop from the sky. By the next morning, approximately 2,000 dead birds lay scattered throughout the town. What could have caused this bleak phenomenon?

Beebe mayor Mike Robertson told press sources that poisoning, illness or disease are not believed to be the culprit. Autopsies will be carried out on dozens of the bird specimens today, and Arkansas Game and Fish Commission ornithologist Karen Rowe stated that the birds showed signs of physical trauma.

"It's important to understand that a sick bird can't fly," Rowe told Time.com. "So whatever happened to these birds happened very quickly. Something must have caused these birds to flush out of the trees at night, where they're normally just roosting and staying in the treetops ... and then something got them out of the air and caused their death and then they fell to earth."

The bewildering number of deceased birds may be explained by fireworks going off in the area, which could have startled the birds from their sleep and caused them to die from stress, Rowe stated.

Another possibility is that the birds were struck by stormy weather as they flew at high altitudes. Such an occurrence isn't rare, and the birds' trauma points to the possibility that "the flock could have been hit by lightning or high-altitude hail," according to Rowe.

But weather anomalies and fireworks aren't the only thing that can wipe out a big group of animals in a single blow. In northwest Arkansas, an estimated 100,000 dead drum fish floated to the surface of a 20-mile stretch of the Arkansas River near Ozark.

"The fish kill only affected one species of fish. If it was from a pollutant, it would have affected all of the fish, not just drum fish," Keith Stephens of the Arkansas Game and Fish Commission told CNN.com, suggesting that some sort of disease is most likely to blame for the mass fish death.

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This article was provided by Life's Little Mysteries, a sister site to LiveScience.